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Block Library
Input Transducer Blocks
LD292 / LD302 - Pressure Transducer
Description
The pressure transducer makes the corrected pressure sensor reading RIMARY_VALUE available
to the AI block. The engineering unit and the primary value range are selected from the XD_SCALE
in the AI block. The units allowed are: Pa, KPa, MPa, bar, mbar, torr, atm, psi, g/cm², kg/cm², inH20
a 4°C, inH2O a 68°F, mmH20 a 68°F, mmH20 a 4°C, ftH20 a 68°F, inHg a 0°C, mmHg a 0°C. The
XD_SCALE range must be inside the sensor range in the unit selected. Note that the XD_SCALE
should be used to cancel out wet-legs etc. instead of calibration. The supported mode is OOS and
AUTO. As the transducer block runs together with AI block, the transducer block goes to AUTO only
if the AI mode block is already in AUTO. The sensor temperature may be read from the
SECONDARY_VALUE parameter.
Warning messages may appear in Primary Value status or in the Block Error in certain condition as
explain below.
Supported Modes
OOS and AUTO.
BLOCK_ERR
The BLOCK_ERR of the transducer block will reflect the following causes:
•
Input Failure – When sensor is disconnected from main electronic board, or the pressure is
higher or lower 27.5% of the sensor limit;
• Out of Service – When the block is in OOS mode.
Primary_Value Status
The PRIMARY_VALUE status of the transducer block will reflect the following causes:
•
Bad::SensorFailure:NotLimited – When sensor is disconnected from main electronic board,
or the pressure is higher or lower 27.5% of the sensor limit;
•
Uncertain::SensorConvertionNotAccurate:NotLimited – when pressure is between 27.5% of
sensor limit and the sensor limit.
Parameters
Idx
Parameter
DataType
(length)
5
MODE_BLK
DS-69
6
BLOCK_ERR
14
PRIMARY_VALUE
Valid
Range/
Options
Default
Value
Units
Store
None
D
Bitstring(2)
None
D/RO
DS-65
XD_SCALE
D
The measured value and
available to the Function Block.
XD_SCALE
S
The High and Low range limit values,
the engineering unit code and the
number of digits to the right of the
decimal point to be used for Primary
Value.
SVU
D
The secondary value, related to the
sensor
E
S
The engineering units to be used with
SECONDARY_VALUE.
OOS, AUTO OOS
15
PRIMARY_VALUE_RANGE
DS-68
29
SECONDARY_VALUE
DS-65
(-40) –100°C
30
SECONDARY_VALUE_UNIT
Unsigned16
°C, °F, °R,K
°C
Description
Indicates the operation
Transducer Block.
mode
of
Indicates the status associated with
hardware
or
software
in
the
Transducer.
status
Legend: E – Enumerated parameter; na – Admensional parameter; RO – Read only; D – dynamic; N – non-volatile;
S - static
Gray Background Line: Custom Parameters
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